Gyroscopic instrument



Sept 9, 1952 P. F. sHlvl-:Rs 2,609,615

GYROSCOPIC INSTRUMENT Filed Sept. 26, 1945 2 SHEETS-SHEET 1 yb/YM' P. F. SHIVERS GYROSCOPIC INSTRUMENT Sept. 9, 1952 2 SHEETS- SHEET 2 Filed Sept. 26, 1945 Patented Sept. 9, 1952 Ui'i'ED STATES PATENT QFFICEl GYROSCOPIC INSTRUMENT Application september 2s, 1945, serial 1,510,618,677

in Which the natural properties of gyroscopes arel utilized to provide a standard of azimuth with respect to which the course of a craft may be compared. While'instrumentsof this typeV are broadly known, `it is an object of my invention to provide .in such an instrument novel features of construction which will make its usemore convenient, its adjustment more simple, and its maintenance easier and more rapid.

It is another object of my invention to provide a directional gyroscope having improved releasably actuated self-centering electrically responsive control members.

It is another object of my invention to provide a directional gyroscope having a graduated-scale and improved illuminating means therefor.

It is another object of my invention to provide a directional gyroscope having a graduated scale and improved means for adjusting the scale to a desired reading while the gyroscope is in operation.

Y A further object of this invention is to provide a directional gyroscope having a readily removable member carrying all elements requiring frequent servicing or'adjustment.

A still further object of my invention is to provide a directional gyroscope havingimproved releasably actuated self-centering electrically responsive remote control members such as potential dividers, together With a graduated scale, a readily removable mem-ber carrying all elements requiring frequent servicing or adjustment, and improved means for adjusting a novelly illuminatedscale to a desired reading-While the gyroscope is in operation.

Various other objects, advantages,- and features of novelty which characterize my invention are pointed out with particularity in the claims annexed hereto-and forming a part hereof. However, for a better understanding of the invention, its advantages and objects attained by its use, reference should be had to the subjoined drawing, which forms a further part hereof, and to the accompanying descriptive matter, in which y I have illustrated and described a preferred embodiment of my invention.

In the-drawings:

Figure 1 is a generally elevational View of the instrument, partly in section, with certain other parts broken away for clarity of illustration;

Figure 2 is a generally bottom View of that portion. of the instrument shown in Figure 1 containedwithin the casing; Y

4 Claims. (Cl. 33-204) 56' natu-re that if the scale is illuminated With light Figure 3 is a bottom view of the removable cover member shown in Figure 1;

Figure 4 is a cross-sectional View of the member shown in Figure 3, the section being taken along the line 4 4 in Figure 3;

Figure 5 is a fragmentary View of a portion of the device shovvn in Figures 3 and 4; and

Figure 6 is a schematic wiring diagram of the electrical vsystem used in this instrument.

Referring now to Figure 1, it Will be seen that my gyroscope is mounted in a casing I0 including a front Wall II, a top I'2, avbottom I3, and side walls I4 which, for convenience, have been made unitary, anda rear Wall I5 upon which the instrument is primarily mounted. Top I2 has an opening IS which is closed by a removable meme ber Il, the latter being held in place by any suitable means, not shown, such as machine screws. The front Wall I I of casing I0 is vprovided with -an opening 2i) in which a transparent disk 2l is maintained by a snap ring 22. A masking member 23, provided with a central index 29, is located behind transparent member 2| for cooperating with a graduated scale presently to be described. Wall I I is also provided with a boss 24, which is traversed by a shaft 25 bearing on its inner end a gear 26 and on its outer end a knob 2l. Knob 2l is provided With an apron 30 in telescoping relation With boss 24, and knob 21, rshaft 25, and gear 26 are assembled into a unitary structure which is capable of movement both axially and angularly. Inward axial movement. of this structure is opposed by a spring 3|.

Rear Wall I5 is mounted tocasing I'il by suitable means not disclosed, and supported by wall 11.5 are an upper bracket 32 and a lower bracket 33. Mounted in bearings 2B in b-rackets 32 and 33, Yfor rotation about a normally vertical axis, is a gimbal ring 34. I Mounted o-n gimbal ring 34 and arranged coaxially about the vertical axis is a ringgear 35. This gear engages a pinion SGcarriedby the shaft of-a motor 3l which is also supported from back Wall I5. Energization of motor Slis thus effective to apply to gimbal ring 34 a torque acting about its Vvertical axis.

The bottom of gimbal ring fljis inthe-shape of a ring 4t so arranged as to be parallel with ring gear 35. Ring d0 is provided with an annu-` lar shoulder 4i, and frictionally engaging .the ring and shoulder is a cup-shaped member 42 of light-transmitting material. The upper outer rim of member 42 carries a translucent scaleV ofI azimuth 43 on an. opaque background of sucha falling upon the scale from within the cupshaped member, the indications are plainly visible from the outside. Member 42 is maintained in proper relationship with ring Iii) and shoulder 4| by a spring member 44 comprising in general an annular portion i5 and four projecting arms 46 having deformed end portions 4l, the whole being fastened to ring 49 by means of suitable machine screws 55. Arms i3 are so formed that when screws 59 are tightened a desirable degree of frictional contact is maintained between member 42 and ring 4U.

Member 42 is also provided with a downwardly projecting gear portion 5|, which is so .located when the device is assembled as to cooperate with gear 26 when shaft 25 is pushed inwardly. Under these conditions, rotation of knob 2l is effective to rotate member 42 about the vertical axis of the gimbal ring 35i, and if gimbal ring 34 is maintained fixed in azimuth, member 42 slips with respect thereto through the frictional connection `inst described.

Also supported upon ring 49 by machine screws 5t is a disk 59 of insulating material carrying a plurality of slip rings 52 for conducting electrical current from the casing to the gimbal ring regardless of the position of the gimbal ring about its vertical axis. Slip rings 52 are energized by brushes 53 which are carried by and insulated from bracket 33, which has not been shown in Figure 2 to avoid unnecessarily complicating the figure. The portion of the simplified circuit energized through slip rings 52 and carried by gimbal ring 34 is shown within dotted box 54 in Figure 6 and will be discussed more fully below.

Pivotally mounted in gimbal ring 34 for rotation in bearings 49, only one of which is shown, about a horizontal axis lying in the plane of the paper and perpendicular to the vertical axis of ring 3:1 is a housing 55 containing a conventional gyroscope rotor including an electric motor for maintaining it in continuous high speed rotation. To avoid complicating the drawing, the housing 55 is not broken away to show the rotor contained within it.

Carried by housing 55 is a resiliently mounted conducting roller 56 which is insulated from the housing and which may make contact with either one of a pair of contact plates 5l and 6B if displaced from its normal position. Plates 5l and 68 are mounted in spaced relation on an insulating member 6|, which projects between them to comprise a compound plane surface. Roller 56 and plates 51 and 69 are displaced from the axis of rotation of housing 55 in gimbal ring 34. The roller rests on the insulating strip between the plates if the housing is in its normal position, While if the housing is tilted in either direction about bearings 49, the roller contacts one of the plates and therefore completes one or the other of two electrical circuits.

The bottom 62 of member 42 is transparent, and mounted-beneath it on bracket 33 is a panel lamp 65. The arrangement, relation, and configuration of the various parts are such that a direct path is available for a beam of light from the filaments of lamp 65 to the inside of scale 43 on member G2. As suggested in the dotted lines in Figure 2, member 23 is so shaped that it conforms Very closely to the outline of member 43 when the instrument is assembled, and thus prevents the passage of extraneous light to scale 43.

Referring to Figure 4, a shaft 8| extends upwardly along the axis of ring 34 and is unitary therewith. Mounted on shaft 8| by a set screw 82 is a flexible coupling member 83 comprising upper and lower disks 8@ and 35 of a ferro-magnetic material and an intermediate leaf 8S. As shown in more detail in Figure 5, leaf 86 is riveted to member near its periphery by rivets 3?, and to member 913 in a similar fashion by rivets 93. By this structure it is possible to provide for a certain amount of movement of member 84 with respect to member S5 although rotational movement between the two members is prevented.

In Figure l, bracket 32 is shown as including a pair of sockets 9| and 82 arranged to receive a pair of. pins S3 yand 94, respectively, projecting downwardly from cover il. Bracket 32 is also shown as supporting a multiple connector for making electrical connection between casing l0 and circuit elements supported on cover Il. As shown in Figures 3 and 4, pins 93 and 94 are suitably embedded in cover i7, which also supports a pair of intertapped resistance windings 96 and 97 which together with a pair of sliders 98 and 99 comprise means for deriving electrical signals from the instrument, in a fashion presently to be described, for the purpose of actuatingsuch a control or indicating device as may be desired. A plurality of contacting pins |94 are embedded in cover I1 and arranged for cooperating with the sockets in member 95 shown in Figure l to make quickly releasable connections between the windings, and their sliders, and a conventional multiple connector ll carried on the back wall of casing l0.

A pivot III is shown as embedded in cover I7, and pivotally supported thereon is a solenoid H2, deriving its energy from two of the pins |04 under the control of a circuit external to the instrument and connected thereto through connector |07. When cover |'i' is assembled to the completed instrument, solenoid H2 is aligned with coupling member 83, so that upon energization of the solenoid, member 84 moves into magnetic engagement with the solenoid. Any relative movement -between gimbal ring 34 and casing I0 therefore results in rotation of solenoid H2 with respect to cover l1.

A pair of arms |20 and |2| are pivotally connected to solenoid H2 as at |22 and contact opposite sides of pin 94 as at |23 and |24. A small spring |25 connects arms |20 and |2| so that in the absence of any other force solenoid H2 Orients itself with respect to pin 94. Any rotating force supplied to solenoid H2 through iexible coupling 83, however, is effective to rctate the solenoid against spring |257 regardless of the direction of the force.

As shown in' Figure 4, sliders 9S and 99 are mounted upon and insulated from the core H3 of solenoid H2 by insulating bracket members |30 and |3|.

Operation Referring to Figure 6, it will be seen that a motor IG having field windings 'H and '12 and an armature 'I3 is energized from a suitable source 74 of alternating current through a pair of the brushes 53 and collector rings 52. To bring about the desired rotating eld, a capacitance is connected in series with one of the windings, and in order to make it possible to balance the gyro housing the capacitance is embodied in two capacitors, one to be mounted on each side of an axis of the gyroscope. It will be understood that-.motorr:comprises the source'of powerfor maintaining'fthe f rotorxof the fgyro :in .continuous high speed rotation.

The second motor fsh'ownii-n I Figure "6 is servomotor 31 Ewhich V.also comprises a 'condenser -mo tor including windings 'l5A and 16,a rotor-11, and ya capacitor 80. Motor. 3J -is energized by means` external to thegyroscopewhich connects conductor -18.f.rom themotor to .conductor l"I9 vfrom the source of alternatingvoltage to perform its function in a conventional Yreversing 'motor-control circuit. controlled .by the position of vroller -56 withrespect to. plates-5'! and 60. When roller 56 is in .Contact With .plate .60., winding 'T6 .of moto'rf31`i's energized 'directly Tthrou'gh .a pair of the collector. rings and brushes 53; whilewinding l5 is 'energized vin the same manner through a condenser 8'0. The necessary rotating field there- Afore is set up vior 'operation .of rotor 'T1 in a -first direction. On the other hand, if roller '56 contacts plate '5-7, thenwinding T5 is energized directly While winding .1"6 yis energized through condenser'', andthe rotating field is set up for energizing rotor H to operate .in the opposite direction.

VIn -the use of vmyjinvention theinstrument is mounted on-the instrument board of an aircraft so that'the indications VVare visible to the pilot, and so that the "axis-off rotation of gimbalring 4S'lli's vertical when vthe cra-ft is in the position of level iiigh't. Suitable electrical connections are made to `connector yH11 to permit energization of the rotor motor, the servomotor, land the solenoid,f'and.to conn'eet `the resistance windings and sliders in appropriate electrical circuits as may befdesired. The circuit is firstcompl'eted'energizing the rotor 'of the gyros'c'o-pe, and lamp 63 may conveniently'b'e illuminated at the same time. It will :be `appr'eciats-rd thatwhile the gyroscopeis coming up'torspeed, it is not possessed of the necessary energy to perform its function, norwillit at rst'have sufcient energy to-remain particularly stable in vany .position as it accelerates. Accordingly, 'during'this Warmingup period solenoid :il I 2 is `maintained :deenergized and therefore lthe -g-yroscope 4is not '.eiective .to control the position of sliders yS3 and y99 with respectY to -the windings of the-potential dividers. lIhe sliders accordingly remain at their central positions under the in-uence of spring 125'. The circuit-to the servornotor-isV alsomaintained dee'nerg'ized during the early warming-up period;

As lthegyroscope rotor approaches its normal speed, the circuit toY servomotor' 3'!Y is independently completed externally of `the gyroscope. Under ordinary conditions,.-a `greater or a less amount oimovement-of the aircraft has taken place since la'st'the gyroscope was energized, 'and this together with the effect of. starting the rotor usually results in-a conditionoithe instrument, whenthe servomot'or is energized, .in which'the airis .o'f .rotation .is .not horizontah This means that "roller 56 is in contact withplate .5J orrplate 6'0, which -re's'ults 'inenergizing moto-r 31 ina first or 4second 'sense depending upon which of theplates 'is 'contacted by the roller. Energiz'a-tion 'of .motor 3T is eiective to supplyfaJ torque to "ring'g'ear .35 throughpinionyand this in turn results in precessive movementv ofthe gyroscope 'about the axis .,pivota'llyl mounting the housing 'in 'the gimbal ring. 'Ilhis Vprecessive movement continuesuntil roller 55 moves off the cond'i'ctin'g` plate 'infquestion to. the `central `inslatin'g strip, when energization--ofthe servomot'or 'is interrupted.

If .the :craftisznow in ;level;flight,.;any .changes in the heading-ofthe craft will'fresult in the movement ofthe index withirespect .tothe-scale so -that -changesi-in' the reading-of the instrument are observed v-by the vpilot. :In order 1 to. coordinatetheindications of .the instrument with the desired course, .thewheading lof the craft is maintained -as desired v-whi'levfknob 2'1 Iis pressed inwardly-un-tilgearaengages with lgear 5|.. Rotation of.-knobf21 s-therea'fter eifectivetorotate member 42 .about the `vertical axisof .the...gyro scope, and thisis continueduntil theinstrument indicateszeroor such other .reading as the pilot desires.

The spring member 4.4.continuously holds the member 4.2 vin friction'al .engagement with ring 4U during the entire time 'that member ,42 Vis 'being rotated .and prevents .separation ofA member 42fromring ED' during such- -resetting operation. Due to the 'ricjtional engagement vbetween member Zandring 4D, the...o`peration.of. knob 2T appiies a torque to gimbal .ringll tending to.

rotate 'it about thevertiCal axis, andto carry the gyroscope Awith it. Any .movement of -the gyroscope, however, must takeY .place .precessively ahoutthepivotal axis ofthe .'houslinggthus.d'is-v placing rollerL56 tocont'act one-ofthe plates-and to .energize servomotor. 31. The .servomotor- .applies a jtorque .to ring 35, opposite. -to .that applied to the -knob 2'1; the power outputl of motor -3'1 is. greater than the `frictional lforce .between memberfliz andring 4D- .Gimbal ring Mandringgear :i5-.are thus maintained `vfixed about .the .vertical axis of the gimbal ring-,.,andthe--graduated member 'is frictionally movedwith respectto thegimbalring until thedesired indicationfis attained.

.By provi'dingthismethod ofadjusting their-1- strument, it will be obviousthatany need .for cagi'ng the .gyroscopeduring adjustmentotthe reading is obvia'ted. Thismeansfthatthegyroscope Visfi'n yful-l controlofthe. instrumentatall times .even during .the adjustment. ofthesetting, and `that complicated and troublesome caging mechanisms are eliminated.

.Having once set the instrument to the desired course, .solenoid H2 is energized externally ofthe instrument. This results in .theattraction oi' disk 84 into intimate magnetic contactwi'ththe solenoid, so that anyr'el'a'tive movement between thefhousin'g 'and 4the .vertical shaft off .the gyroscopeappears yas rotation of the solenoid With respect to the cover, and thereforea's movementp'f the sliders wi-threspecttoithe resistance Windi-ngs. It will Aof course be 'appreciated that 'as such'displac'ement takesfplace, -spring I2f5 "is extended and this in turn effects 'aqrotatingytorque upon/the gy-roscope about-its vertical axis; 'but thisis immediately-opposed as previously .desc-r'ibedrby the effect yof Aservcmotor andthe gylroscope -retalinsf'itsaccuracy. i

'lit will also -be immediatelyapparen-t that this instrument iis Snotdesigned-for Ycontrol ci sliders B8-'and Si Q'With -respe'ctfto their Windingsthroughout=aB69 'turn ofthecraft'lin azimuth, butrat'her to.. fa ."control iof the ysliders/in 'response #to -fsmfall devradensz ofV the .craft :in one direcdcrlor the other v a .predetermined :or zer@ course.' if it is vdesired to makefaiturn olf? considerable-'=ma`g'- nitride, or 'to change the course-permanently by even a small =angle,.so'1enoid 5| |22 isdeenergized, thus releasing Vthe control.' o'fl'tlie :gyro's'eope `over thesliders which iare recentered spring 51125 if theyare out-of centen-andW-henithe.newioourse is attained the solenoid is Once:morsienergized so that the control of the gyroscope over the potential dividers is again established.

Numerous objects and advantages of my invention have been set iorth in the foregoing description, together with details of the structure and function of the invention, and the novel features thereof are pointed out in the appended claims. The disclosure, however, is illustrative only, and I may make changes in detail, especially inmatter of shape, size and arrangement of parts, within the principle of the invention, to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.

Iclaim as my invention:

1. 4In a device of the class described, in combination: a gyroscope having a spin axis and cardanic mounting means; a casing means enclosing'and supporting said cardanic mounting and said gyroscope; a removable cover for said casing; means carried by said cardanic mounting means for altering the condition of energization of an electric circuit in response to departure of said spin axis from a normal orientation; vsignal producing means carried by said cover; means releasably coupling said signal producing means to said cardanic mounting means and actuating said signal producing means through movement of said cardanic mounting means; said coupling comprising a ferro-magnetic member and an electrically energizable member; and means mounting said ferromagnetic member in angularly rigid and axially movable relationship to one of the axes of said cardanic mounting means.

2. In a device of the class described, in combination: a gyroscopehaving a spin axis and cardanic means mounting said gyroscope for a predetermined nomal orientation of said axis; a casing for said gyroscope and cardanic means; means including a motor means for applying a torque between said casing and said cardanic mounting means; means responsive to a departure of said axis from said normal orientation for controlling said motor means to precessibly return said axis to said normal orientation; an indicating member directly mounted on said cardanic mounting means in frictional engagement therewith, said indicating means being graduated and provided with indicia indicating angular displacement; means for continuously holding said indicating member in operative frictional engagement with said cardanic mounting means .with suflicient force that said indicating member can not be slid with respect to said cardanic mounting means Without an appreciable tendency toward precessional movement of said vgyroscope; an index carried by said casing for visual cooperation with said graduations on said indicating member; and means mounted on said casing and adapted to selectively engage said indicating member without interrupting the gyroscopic stability of the gyroscope and rotate theindicating member against the restraining effect of said frictional engagement so as to cause sliding relative movement between said indicating member and said cardanic mounting means, said motor means having a torque output sufficient to overcome said frictional engagement between said indicating member and said cardanic mounting means to maintain said gyroscope in a substantially normal operation in its predetermined orientation.

3. In a device of the class described, in combination: a gyroscope having a spin axis and cardanic means mounting said gyroscope for a predetermined normal oientation of said axis; a casing for vsaid gyroscope and cardanic means; means including a motor means for applying a torque between said casing and said cardanic mounting means; means responsive to a departure of said axisfrom said normal orientation for controlling said motor means to precessibly return said axis to said normal orientation; a cylindrical indicating member'surrounding and directly mounted on said cardanic mounting means in frictional engagement therewith adjacent the periphery of the cardanic means, said indicating means being graduated and provided with indicia indicating angular'displacement; means for continuously holding said indicating member in operative frictional engagement with said cardanic mounting means with suiiicient force that said indicating member can not be slid withrespect to said cardanic mounting means without an appreciably tendency toward precessional movement of said gyroscope; an index carried by said casing for Visual cooperation with said graduations cn said indieating member; and means mounted on said casing and adapted to selectively engage said indicating member without interrupting the gyroscopic stability of the gyroscope and rotate the indicating member against the restraining effect of said frictional engagement so as to cause sliding relative movement between said indicating member and said cardanic mounting means, said motor means having a torque output sufcient to overcome said frictional engagement between said indicating member and said cardanic mounting means to maintain said gyroscope in a substantially normal operation in its predetermined orientation.

4. In a device of the class described, in combination: a gyroscope having a spin axis and cardanic means mounting said gyroscope for a predetermined normal orientation of said axis; a casing for said gyroscope and cardanic means; means' including a motor means for applying a torque between said casing and said cardanic mounting means; means responsive to a departure of said axis from said normal orientation for controlling said motor means to precessibly return said axis to said ncrmal'orientation; a cylindrical, light transmitting, indicating member surrounding and directly mounted on said cardanic mounting means in frictional engagement therewith adjacent the periphery of the cardanic means, said indicating means being graduated and provided with indicia indicating angular displacement; means for continuously holdingrr said indicating member in operative irictional engagement with said cardanic mountlng means with sufficient force that said indicating member can not be slid with respect to said cardanic mounting means without an appreciable tendency towards precessional movement of said gyroscope; an index carried by said casing for visual cooperation with said graduations on said indicating member; means mounted on said casing and adapted to selectively engage said indicating member without interrupting the gyroscopic stability of the gyroscope and rotate the indicating member against the restraining eiect of said frictional engagement so as to cause sliding relative movement between said indicating member and said cardanic 9 mounting means, said motor means having a torque output sucient to overcome said frictional engagement between said indicating member and said cardanic mounting means to maintain said gyroscope n a substantially normal operation in its predetermined orientation; and light means located Within said casing and so positioned with respect to said indicating member that the same is illuminated as from within.

PAUL F. SHIVERS.

REFERENCES CITED The following references are of record in the 111e of this patent:

UNITED STATES PATENTS Nulnbel 15 Number Great Britain June 12, 1940 

